An Etymological Dictionary of the German Language/wetzen
wetzen, vb., ‘to whet, sharpen,’ from MidHG. wętzen, OHG. węzzen (from *hwazzjan), wk. vb., ‘to sharpen’; comp. Du. wetten, AS. hwęttan, E. to whet, OIc. hvetja, ‘to sharpen.’ A common Teut. wk. vb., properly strong. The Teut. strong verbal root hwat, from Aryan kwod (by gradation kud), seems to be equiv. to the Sans. root cud, ‘to whet, sharpen, set on fire, incite’ (comp. AS. hwęttan, OIc. hvetja, ‘to excite, incite,’ prop. ‘to sharpen’). The older Teut. periods preserve the adjs. hwassa- (Goth. hwass, OHG. and MidHG. was) and hwato- (AS. hwœt, OHG. waȥ), ‘sharp,’ from the root hwat.